Originally Posted by Hopinater
I think it's what Tom mentions above. It's about SPL and perhaps the frequencies affecting people in a certain way. If they are use to a ported sub that drops off dramatically after 22Hz but then encounter a sealed sub that digs much deeper with more SPL they may (erroneously) decide that sealed subs are the issue where as really it's the frequency and SPL of the sub involved.
But I do know that ported subs can affect people as well. Maybe this example will help. But first let me set the stage. For a person to enter my HT you have to walk right in front of the subs. So if you want to talk to me you have to enter the room and stand behind the couch to get my attention, that put's you about six to seven feet in front of my subs and smack dab in between them. That's a hot zone! Twice she made the same mistake... once she stood right in-between the dual TV36 iPals and the other time she stood right in-between the dual 2400ULF's. Not so bad except the mistake she made was doing it right as a huge ULF bass moment hit. Just bad timing. Both times she said the pressure made her ears hurt. I don't recall her ever complaining that the higher tuned V3601 hurting her ears and she stood in that spot many times.
Anyway, I think it's the lower frequencies playing at loud levels. Or maybe it's something else all together.
I think that it is definitely low-frequencies playing at higher SPL's. But, I also think that sealed subs can be a little more insidious about the whole ear pressurization thing than ported subs can. When ported subs are able to hit frequencies below the pressure vessel gain frequency in a room, the tactile response can be very overt at higher sound levels. We may feel those stronger TR sensations and not want to crank the subs any more.
With sealed subs, especially in a smaller sealed room, it may not take as much low-frequency SPL to create pressure on the ear drums as it would in an open room, but we may also not have the same early warning of strong low-frequency tactile sensations that we would with ported subs. I have a large room, but I can seal it pretty tight when I want to. Even with ported subs, I can create that pressurization feeling when I want to. (I actually don't like that feeling in my HT.) But, I will already be experiencing a lot of low-bass TR before I get to that point, and I'm not as likely to keep cranking the bass or the overall volume level.
I think that sealed subs may just sneak up on us a little more sometimes, especially if the room is sealed to start with, and if we have enough SPL down in the 15Hz and lower range. Of course, it also takes the right kind of low-bass content to start with, and as others have noted, our susceptibility to those pressurization sensations may vary quite a bit.
For instance, I think I have always been more susceptible to ear drum pressure, from cabin pressurization on airplanes, and from scuba diving, than the average. So, it makes sense that similar SPL-driven cabin pressure might be more noticeable, or less pleasant, to people with that particular susceptibility.